The entire episode surrounds Holmes’ ignoring Mycroft‘s (Mark Gatiss) advice and going after powerful blackmailer Charles Augustus Magnussen (Lars Mikkelsen) who seemingly has everyone in England under his thumb. Wasting no opportunity to show off how vile and intelligent Magnussen is, the episode gives us everything from the villain outsmarting Holmes to licking the face of his newest blackmail victim in public as a display of his power.

Holmes is shot while investigating Magnussen, and the reveal of those events will put a strain on Watson’s marriage when Sherlock’s partner learns that not only did Mary shoot his best-friend but she is also a former spy who Magnussen had been leveraging. Eventually the episode boils down into an one-on-one battle of wills between Holmes and Magnussen which the world’s greatest detective looses. The subsequent events define the phrase “cheap-way out” as the season finale struggles to a close with Holmes arrested and facing deportation before offering one final reveal and setting up the next series of episodes.

Although parts of the episode are well-done, and the explanation of why Watson would find someone like Mary to be his perfect match make sense, the execution and the writing leave much to be desired. Magnussen is too grand a villain to be introduced, made victorious, and dispatched in a single episode. Other than the fact that these are characters calling each other Holmes and Watson there’s little use of the detective’s considerable skills (other than unmasking Mary for John’s benefit). And the tease of the return of Moriarty (a storyline that’s already run its course) isn’t an enticement, at least for me, for the show’s eventual return.

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Wonderful short review here! I love this episode and its my favorite in this season and second favorite in this whole series, however, its only redeeming quality apart from the obviously brilliant acting and good, albeit imperfect, writing was Magnussen. I loved him and hes my favorite villain in the whole series. Seeing him utterly and embarrassingly defeat Sherlock at his own game with such ease made my day and it was well deserved. It also added a well needed sense of realism to the show that it lack up till this episode since the good guys don’t always win. The portrayal of the Mind Palace on Magnussen and Sherlock’s parts in this was genius too. However, this episode’s reveal of Mary being a psychotic murderer and the new traits thereof she showed totally destroyed any respect and liking of the character I had up until now.